Cooperative Effect of Li Content and Equal-Channel Angular Pressing on Microstructure and Mechanical Properties of Al-Mg-Li Alloy

Autor: Ting Yuan, Jinghua Jiang, Yuna Wu, Zhipeng Yuan, Aibin Ma, Yuchun Yuan
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Metals, Vol 9, Iss 8, p 840 (2019)
Druh dokumentu: article
ISSN: 2075-4701
DOI: 10.3390/met9080840
Popis: This paper investigated the cooperative effects of Li addition and warm Equal Channel Angular Pressing (ECAP) on improving the mechanical properties of an Al-Mg-Li alloy for further weight reduction. The results showed that more Li addition could obviously refine the grains of the as-cast alloy and reduce its density value to only 2.37 g/cm3 when Li content reached 2.5% (about 12.6% lighter than commercial Al alloys). It also had a pronounced influence on the precipitations in the Al-5.5Mg-xLi-0.1Zr alloy, i.e., the number density and size of Al2MgLi and δ’-Al3Li phases. The yield strength of the as-cast alloy was increased with increasing Li, but the elongation deteriorated due to primary network intergranular Al2MgLi and more δ’ particles in the high Li-containing alloy. The warm multi-pass ECAP process was found to simultaneously improve the strength and ductility of the Al-Mg-Li alloys, and greatly alleviate the detrimental effect of Li addition on the elongation, thereby making the ultrafine-grained (UFG) alloys, a good combination of lightweight and high performance, very attractive for aerospace applications for much higher specific strength than both Al matrix composites and Mg alloys.
Databáze: Directory of Open Access Journals